301 redirect - good for SEO?

I have a main blogger site with ~15 niches and I want to rank it on google but I find it pretty hard because I can't fully do 100% GOOD on-page seo(because of not having a EMD).
So I wanted to buy EMD for each niche and then do 301 redirect to my blogger.

I have few questions:
1. Is it a good thing to do?
2. Will the site rank on google?
3. Which site should I bring backlinks to, the blogger or the EMD?
4. Should I buy hosting per EMD niche and build a site ? will it have the same effect? since I can't buy so many hostings...

Thanks in advance for the helpers,
Chen

1. Yes 301 is good.
2. Ranking depends on how your overall SEO strategies plays out.
3. I will say the EMD, since you will be more protected.
4. You don't need to buy hosting for each EMD, you can use one host, but if you feel a need, you can put some bunch on different host.

theirs a recent thread on here about a case study with 301 redirects, check it out

Thanks for answering guys
Then you think I should buy emd for each niche and do 301 redirect to my old site?

what do you think will be better having a site uploaded to the emd or having a 301
redirect ? I mean the 301 redirect is cheaper ... But is it more effective ?

If you buy a new EMD, which has no power how can that new domain with 0 backlinks and 0DA and 0PA can help your website to rank higher in search engine? Think dude Think...

since it is EMD and I will build it backlinks and all ... my question is if it is 301 redirect to another page will it be able to rank?
or should I build a site for each niche with hosting and etc?